Calendering



Dec. 22, 1936. w w spoo 2,065,032

CALENDERING. DRYING, OR LIKE TREATMENT OF MATERIALS Filed Sept. 8, 19342 Sheets-Sheet l Dec. 22, 1936. SPOONER 2,065,032

CALENDERING. DRYING, OR LIKE TREATMENT OF MATERIALS Filed Sept. 8, 19342 Sheets-Sheet 2 jPvme/z rofr Patented Dec. 22, 1936 UNITED STATESPATENT. OFFICE GALENDEBING, DRYING, OR LIKE TREAT- MENT OF MATERIALSWilliam Wycliffe Spooner, Ilkley, England 9 Claims.

The present invention relates to the calenderv ing, drying and liketreatment of materials such as paper, board or the like.

A method of drying paper, board or like material according to thepresent invention consists in applying one side of the paper to a heatedmetallic surface and applying a drying fluid at a temperature higherthan that of the paper in the form of a number of high velocity jetsdirectly on to the other side of the paper so as to set up a rapidconvectional drying eflect in addition to the conductional drying effectof the metallic surface.

Preferably the drying fluid is circulated in a closed path and isprojected on to the paper whilst flowing in such closed path.

The fluid is projected on to the paper at an angle thereto, that is notparallel thereto.

The drying fluid may be air, gas, or superheated steam. The metallicsurface may be formed by the periphery of a drying cylinder or roll oralternatively it may be formed on one side of a metallic conveyor bandpreferably an endless conveyor band to which heat is applied on the sideremote from the paper. Preferably each jet of fluid extends continuouslyacross the width of the paper and the width at projection may beslightly greater than the width of the paper.

It is advisable to arrange for the projection of the jets of fluid on tothe paper to take place within a hood extending over a portion of thepath of the paper, so that if desired, the fluid can be drawn by meansof a fan from the hood and reprojected in jets on to the paper so as tocause flow of the fluid in a closed path and means may be provided foradmitting fresh fluid to the closed path and for rejecting part of theused fluid. Where a hood is employed this may be located adjacent theperiphery of a drying roll.

The speed of the fluid may lie between 10 and 32 feet per second. Speedsless than 10 feet per second may be employed where it is desired thatthe drying shall take place at a comparatively slower rate.

A paper-making machine according to the present invention may includeone or more cylinders or rolls over which the paper web engages and acasing for the reception of the drying fluid which is located adjacentthe path of the paper and has convergent nozzles directed towards thepath of the paper for projecting the drying fluid in high velocity jetson to the paper at an angle thereto.

A hood may be arranged over a portion of the paper path to enclose saidcasing and a fan or impellor may also be located within the casing. Amotor for driving the fan may be mounted on a wall of the casing and mayhave its axis parallel with the paper web or at right angles thereto.

If desired, the fan may be mounted at some distance from the casing andmay be connected thereto by suitable ducts.

Thus, the fan may draw the drying fluid from the hood and may dischargethe same to the casing.

A suitable heater may be provided for warming the fluid between theimpeller and the said casing. The hood may be hinged about an axisextending widthwise of the casing to enable it together with the casingto be displaced from the paper for inspection purposes.

The invention is very particularly applicable ,to paper-making machinesof the M. G. type in which case the hood is arranged over a portion ofthe periphery of the drying cylinder. If desired, a single fan andheater and nozzle casing may be arranged within a single hood and anumber of such hoods may be provided on a single M. G. cylinder, butalternatively one hood extending over a considerable portion of theperiphery of the drying cylinder may enclose a number of fan heater andnozzle casing assemblies, or again a number of nozzle casings locatedwithin a single hood may be fed from a single fan through one or moreheaters. The hood may completely enclose the fan, heater and casing, butin the case where air is employed as the drying fluid an opening oropenings may be provided in the casing to permit admission of fresh airto the hood and for the discharge of used air.

The invention may also be applied to the cylinders of a Fourdriniermachine where the paper is not covered by felts and if desired the fluidmay be projected on to the paper in a region where it forms a pocket asit passes over three consecutive rolls or cylinders having their axestriangularly disposed.

One form of construction according to the invention as applied to an M.G. cylinder is shown in the accompanying drawings in which:-

Figure 1 is a front elevation with half of the hood removed.

Figure 2 is a side sectional view on the line A--A of Figure 1 butshowing only part of the drying cylinder.

Figure 3 is a sectional view on the line 3-3 of Figure 2.

A hood I whose side walls are built up of plates 2 extends over aportion of the periphery of a drying cylinder 3,"and is hingedly mountedand supported through a hinge 4 by Bracket members 5. A fan 6 locatedwithin the casing and driven by a motor I is connected through a duct 8with a heater '9, the duct 8 having guide plates or vanes Ill at its endnear the heater for the purpose of distributing the drying fluidsubstantially uniformly through the heater. The heater is connected to acasing ll having two sets of ve-.

locity nozzles l2, l3 formed in its face the nozzles l2, l3 beinginclined at an angle towards the paper and directed towards one another,that is towards the centre of the casing.

It will be appreciated that the drying fluid in the arrangement shown inthe drawings will circulate from the fan through the duct 8 to theheater 9 through the casing II and nozzles l2, l3 on to the paper, andthence into the hood, and back to the fan. An outlet for the dischargeof part of the drying fluid in circuit is provided at M and controlledby a valve l5 shown diagrammatically.

Means not shown are provided for supplying fresh fluid to the circuitand the fresh fluid may be supplied either directly to the heater or tothe eye of the fan. If desired, the fan may be provided with anadditional set of plates located nearer to the motor than the rotorshown in the drawings'for the purpose of drawing inextra fluid. Theheater is preferably fed with steam by an inlet IS the outlet from theheater being shown at l1.

In the arrangement shown in the drawings the motor! is secured on thetop or side wall of the hood, but if desired it may be secured for thesake of convenience in an end wall of the hood, the position of the fanbeing correspondingly altered.

I declare that what I claim is:

1. A machine for paper making including at least one heated metallicmember over which the paper is conveyed, at least one hood extendingover a portion of the path of the paper on said metallic member, acasing between said hood and said metallic member having a wall adjacentthe path of the paper and having groups of velocity nozzles in saidwall, the nozzles-of one group being oppositely inclined with respect tothe nozzles of an adjacent group, and an impeller adapted to draw dryingfluid from said hood and to discharge the fluid to said casing forejection through said nozzles onto the paper.

2. A machine for paper making including atleast one drying cylinder overwhich the paper is conveyed, at least one hood extending over a portionof the path of the paper on said drying cylinder, a casing between saidhood and said drying cylinder having a wall adjacent the path of thepaper and having groups of velocity nozzles in said wall, the nozzles ofone group being oppositely inclined with respect to the nozzles of anadjacent group, and an impeller adapted to draw drying fluid from saidhood and to discharge the fluid to said casing for ejection through saidnozzles onto the paper.

3. A machine for paper making including at least one drying cylinderover which the paper is conveyed, at least one hood extending over aportion of the path of the paper on said drying cylinder, a casingbetween said hood and said drying cylinder having a wall adjacent thepath of the paper, said wall having spaced transverse velocity nozzlesprojecting therefrom to form transverse passages along said wall betweenthe nozzles, and an impeller adapted to draw drying fluid from said hoodand to discharge'the fluid to the casing for ejection through the saidnozzles onto the paper, the fluid being adapted to travel along saidtransverse passages between the nozzles on its return to the impeller.

4. A machine for paper making including at least one heated metallicmember over which the paper is conveyed, at least one hobd extendingover a portion of the path of the paper on said metallic member, acasing carried by said hood and having a wall adjacent the paper on saidmetallic member, velocity nozzles in the said wall of said casingdirected toward the paper, an impeller adapted to draw drying fluid fromsaid hood and to discharge the fluid to said casing for ejection throughsaid nozzles onto the paper, a duct leading from said impeller to saidcasing for conveying the drying fluid, and a heater arranged in saidduct for heating the fluid before its entrance into said casing.

5. A machine for paper making including at least one heated metallicmember over which the paper is conveyed, at least one hood extendingover a portion of the path of the paper on said metallic member, acasing carried by said hood and having a wall adjacent the paper on saidmetallic member, velocity nozzles in the said wall of said casingdirected toward the paper, an impeller adapted to draw drying fluid fromsaid hood and to discharge the fluid to said casi for ejection throughsaid nozzles onto the paper, a duct leading from said impeller to saidcasing for conveying the drying fluid to the casing, a heater arrangedin said duct immediately before its entrance to said casing, anddistributing plates arranged in said duct in advance of said heaterwhereby to uniformly distribute the drying fluid over the heater duringits passage therethrough.

6. A machine for paper making including at least one heated metallicmember over which the paper is conveyed, at least one hood extendingover a portion of the path of the paper and hinged to the machine, acasing between said hood and said metallic member having a wall adjacentthe paper, velocity nozzles in said wall of said casing directed towardthe paper, and an impeller adapted to draw drying fluid from said hoodand to discharge the fluid to said casing for ejection through saidnozzles onto the paper.

7. A machine for paper making including at least one drying cylinderover which the paper is conveyed, at least one hood extending over aportion of the path of the paper and hinged to the machine about an axisparallel to the axis of said drying cylinder, a casing between said hoodand said drying cylinder having a wall adjacent the paper, velocitynozzles in said wall of said casing directed toward the paper, and animpeller adapted to draw drying fluid from said hood and to dischargethe fluid to said casing for ejection through said nozzles onto thepaper.

8. A machine for paper making including at least one drying cylinderover which the paper is conveyed, at least one hood extending over aportion of the path of the paper on said cylinder and having the edgesof the side walls thereof curved to correspond to the curvature of suchcylinder, a casing carried by said hood between the side walls thereofand having a similarly curved wall adjacent the path of the paper,velocity nozzles in said wall of said casing directed toward the paperand an impeller adapted to draw drying fluid from said hood and todischarge the fluid to said casing for ejection through said nozzlesonto the paper.

9. A machine for paper making including a drying cylinder over which thepaper is conveyed, a hood having the side walls thereof curved tocorrespond to the curvature of said cylinder, said hood being hinged tothe machine to permit angular displacement relative thereto. a casingcarried by said hood within the side walls thereoi and having a curvedwall adjacent and parallel to said cylinder, velocity nozzles in saidcurved wall of said casing directed toward the paper, an impellercarried by said hood and adapted to draw drying fluid from the hood, aduet located entirely within the hood and leading from said impeller tosaid casing, distributing plates located in said duct for uniformlydistributing the drying fluid passing therethrough, and a heater locatedin said duct between said distributing plates and said casing wherebythe drying fluid is uniformly heated before it passes into said casing.

WILLIAM WYCIJFElEi SPOONER.

